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Lc_shi
17-12-2007, 07:35 AM
Hi dear sirs
Recently I'm talking with an ice storage energy saving company to introduce their tech into my area market. The business model is "zero investment" cooperation. The ice storage company get all the things done and then share the savng money with the end user within a negotiated time period (5~10 years). It's said ESCo is a mature business model in EU & USA.
I hope to get some comment from the experienced guy here. Thanks in advance!:)

regards
LC

Sergei
17-12-2007, 06:19 PM
I just didn't get it. This company saves energy or stores the ice. What is the function of end user?

Lc_shi
19-12-2007, 09:56 AM
sorry to not make it clear.

It's the retrofit of the existing chiller system to ice storage chiller system to use night low rate electricity to cut air conditioning electricity bill down. It's called energy management contract (EMC).

Hope I make it more clear.

thanks

LC

brian_chapin
19-12-2007, 01:43 PM
I believe he is talking about an Energy Services Company.

http://www.naesco.org/about/esco.htm

Basically, they identify savings. They pay for the equipment, installation and sometimes the maintenance to realize those savings. In return, they get the value of the energy savings until the contract runs out.

If for some reason the savings don't appear then they are stuck with the bill for the equipment. If the savings are in excess of what you thought they would be, the Energy Service Company could end up getting 2x or more the value of the equipment they provided.

Sergei
19-12-2007, 04:14 PM
I read that some companies in A/C businesses can do this type of contracts, because they can estimate potential power use. It is very difficult to do these estimations for industrial refrigeration plants.

US Iceman
19-12-2007, 08:28 PM
If the discussion is indeed about energy services, the concept originated in France I believe. It's called chaffauge (I think that's spelled right).

Someone owns an operates the cooling equipment for a profit while the user is billed for cooling or heating supplied.

It's a very interesting concept and yes, it does take a lot of time to estimate for an industrial refrigeration system.

Difficult, yes...impossible, no.

Peter_1
19-12-2007, 10:19 PM
I think the correct word should be chauffage but this is the translation for heating.
I think chaffauge doesn't exist.
These services exist in Belgium as long as I can remember (at least 25 years)

US Iceman
19-12-2007, 10:23 PM
I think you are correct Peter. The word was actually used for heating, but the principle has been applied to cooling and refrigeration also.

Sergei
21-12-2007, 04:50 PM
If the discussion is indeed about energy services, the concept originated in France I believe. It's called chaffauge (I think that's spelled right).

Someone owns an operates the cooling equipment for a profit while the user is billed for cooling or heating supplied.

It's a very interesting concept and yes, it does take a lot of time to estimate for an industrial refrigeration system.

Difficult, yes...impossible, no.
Everything is possible. Who is going pay for this? To save $100,000 of energy cost somebody can invest $200,000 or just $10,000. It is huge difference. I believe in smart cost effective energy savings.

Peter_1
21-12-2007, 08:17 PM
Everything is possible. Who is going pay for this? To save $100,000 of energy cost somebody can invest $200,000 or just $10,000. It is huge difference. I believe in smart cost effective energy savings.

Who is going to pay this you ask: he/she who wants to save money.
If I can save 100/year and have to invest 200, then a profit/costs calculation isn't even needed.
Even if I should have to invest 500 to save 100/year, then this is still a big saving.
And you can multiply these figures with thousand or billions and they may be in Euros or Dollars, doesn't make a difference.

US Iceman
22-12-2007, 03:11 AM
I have a friend who has been doing this for many years on refrigeration systems and this pays for his retirement. :cool:

Sergei
22-12-2007, 05:44 PM
Who is going to pay this you ask: he/she who wants to save money.
If I can save 100/year and have to invest 200, then a profit/costs calculation isn't even needed.
Even if I should have to invest 500 to save 100/year, then this is still a big saving.
And you can multiply these figures with thousand or billions and they may be in Euros or Dollars, doesn't make a difference.
I think that 2 years payback is a good investment. However, end users have a different logic. Recently, I proposed to one maintenance manager to save $20,000 of energy costs without any investment. Free energy savings. Payback is less than 1 second. He asked me one question. Did you do this savings for anybody else in our company?....

Sergei
22-12-2007, 05:50 PM
I have a friend who has been doing this for many years on refrigeration systems and this pays for his retirement. :cool:
I believe that your friend didn't run energy services in industrial refrigeration. Many ways can be used to save energy(optimization, design, PLCs etc.). What did your friend do to save energy?

EmCoastHVACR
27-12-2007, 11:35 PM
Cost-effective ice storage depends on the tariffs the utility provides.

Ice storage is usually cost-effective when building experiences a high load for a short duration; for example, Churches or places of assembly are areas to investagate.

US Iceman
28-12-2007, 08:08 PM
I believe that your friend didn't run energy services in industrial refrigeration. Many ways can be used to save energy(optimization, design, PLCs etc.). What did your friend do to save energy?

He bought the entire refrigeration system from the facility owner. Then he improved the energy use and how the system operated. He paid for the electricity to run the system himself, and sold cooling back to the facility.

He made the money on the difference of what it cost the owner to produce the cooling versus what my friend paid for the energy used (after he changed the system to be more efficient).

Sergei
28-12-2007, 10:56 PM
He bought the entire refrigeration system from the facility owner. Then he improved the energy use and how the system operated. He paid for the electricity to run the system himself, and sold cooling back to the facility.

He made the money on the difference of what it cost the owner to produce the cooling versus what my friend paid for the energy used (after he changed the system to be more efficient).
This approach is new for me. Someone should be sure that refrigeration load won't increase.

wambat
29-12-2007, 12:21 AM
In the County of Los Angeles, in one of the biggest prisons we installed a thermal energy system using centrifugal compressors which we ran at night. We found that the efficiency of the air conditioning chillers coefficient of performance (COP)was acceptable because in practice, the thermal storage systems could make chillers more efficient because heat was discharged into colder nighttime air rather than warmer daytime air. This was a partial storage system which minimized capital investment by running the chillers 24 hours a day. At night they would produce ice for storage, and during the day they would chill water for the air conditioning system, their production augmented by water circulating through the melting ice. This system usually ran in ice-making mode for 12 to 16 hours a day, and in ice-melting mode for 8 hours a day. The capital expenditures were minimized because the chillers were just about 50% of the size needed for a conventional design. The ice storage was sufficient for storing half a day's rejected heat. We always had redundency built into our systems for emergency repairs (have to provide adaquite living conditions for the inmates...don't you know) :( :D

Lc_shi
02-01-2008, 03:55 AM
Here is a successful company to run water storage system to cut elctricity bills in our country. It's said the waer thermal storage system can accomodate cooling and heating loads which is better than ice storage one.

Josip
02-01-2008, 01:50 PM
Hi, Lc_shi :)


Here is a successful company to run water storage system to cut elctricity bills in our country. It's said the waer thermal storage system can accomodate cooling and heating loads which is better than ice storage one.

Interesting...but water can exist from 0*C up to 100*C....and we need a huge volume (storage) and I think it cannot be a pure water like in ice storage systems....

....please, can you provide some more info about...link maybe...

Best regards, Josip :)

US Iceman
02-01-2008, 04:59 PM
If you are planning on "hot" storage then ice is not the answer. It's incompatible of course.

Water storage requires extremely large volumes to meet the required loads. Also, you have to spend considerable time in designing the water storage tank for chilled water. A thermocline develops in the tank (for cold water) and this needs to remain undisturbed, otherwise you risk a mixing problem in the chilled water storage. This could cause a loss of cooling capacity being stored.

You might want to look at some of the storage possibilities using a salt solution for hot storage and use ice for the cooling requirement.

Lc_shi
03-01-2008, 08:28 AM
Hi sirs
It's one company engaging in this field and for your reference.

http://www.poweru.cn/English/index.asp

regards
LC

IGLOO
04-05-2008, 10:38 PM
Hi ppl.
I understand the concept of selling cooling and all.I would really appreciate it if you guys can give me ideas on how to save energy on a refrigeration plant.Whether its on a Ammonia or ***** plant.Making your plant more efficient by running at optimal conditions as well as different improvements like controllers and drives.Where could i search for ideas and how do i present it too my customers so they can see that there will be a saving in energy costs.South Africa is becoming rediculous with the price of electricity and i believe each plant can be more efficient and cheaper to run...